#include <fcntl.h>
#include <termios.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/select.h>
#include <sys/types.h>
#include <sys/time.h>
struct termio //串口设置结构体
{  
	unsigned short  c_iflag;  
	unsigned short  c_oflag;
	unsigned short  c_cflag;
	unsigned short  c_lflag;    
	unsigned char   c_line;     
	unsigned char   c_cc[8];      
};
int open_usb(char *dev);
